1. Field of the Invention
This invention relates generally to waste water treatment systems for the biological treatment of organic waste material and, more particularly, it relates to waste water treatment systems which utilize a "wetland bioreactor treatment cell" for the biological treatment of organic waste material. The wetland bioreactor treatment cell system of the present invention is fully acceptable for use in cold climates as well as all other moderate, temperate, or tropical climates.
2. Description of the Prior Art
The treatment of high-strength (i.e., septage and primary organic waste effluent flows/solution) wastes having widely variable total solids, i.e., 2,000 mg/l to 150,000 mg/l total solids, and soluble organic and inorganic nutrient loads of carbon, nitrogen, and phosphorous has become increasingly challenging in many regions throughout the world. The difficulties in treating such waste waters are mannified in some locations, especially in cold climates, and particularly in non-industrialized nations and rural areas that cannot be economically served by conventional expensive centralized waste water collection and treatment facilities. Moreover, many rural municipal and publicly owned waste water treatment facilities are unable to accept such high strength waste, especially septage, because the treatment facilities are not designed to effectively separate and treat these high-strength anaerobic organic waste waters that have widely fluctuating physical/chemical characteristics.
Known methods and systems for treating organic waste water such as septic tank waste water (septage), feed lot waste waters and food processing facility waste waters have several drawbacks. Traditionally, such high strength organic waste water treatment processes initially involve a solid/liquid separation stage. Typically, such approaches remove a substantial portion of the solids which are then dried to cake and composted, incorporated into soil, combusted or discarded to landfills, as dictated by representative sampling. The remaining wastewater liquid is then treated separately, stored and tested before being discharged, or sent to an appropriate waste water treatment or internment facility. The separate treatment of the solids and liquid waste waters thus often involves considerable additional testing, handling and management costs. These costs are further compounded by the large volumes and variable solids loads of such organic wastes. As a result, conventional centralized treatment facilities are expensive to capitalize, difficult and often unpleasant to operate and aesthetically unacceptable in surrounding environments.
Most conventional liquid waste water treatment processes utilize time and energy intensive chemical and biological digestive systems in order to render the organic waste water suitable for discharge. Such processes, however, are an expensive way to treat waste waters due to the quantity of staff time, electrical energy and chemical reagents which must be used in order to effectively respond to and treat massive variations in volume and pollutant loads. Moreover, chemical and/or mechanical treatment of waste waters can result in deleterious impacts on the environment, as such systems are especially vulnerable to upset and failure, known as "shocking", when subjected to intense loading. The chemical treatment of waste waters also necessitates additional risks implicit in the manufacture and storage of treatment and disinfecting chemicals.
Yet further, biological or "bioremediation" processes have been proposed for treating organic wastes, which include both exclusively biological and hybrid chemical/biological waste water treatment methods. Hybrid waste water treatment processes have many of the environmental and monetary cost drawbacks of mechanical and chemical treatment processes. Many of the proposed bioremediation processes also utilize solids separation and prohibitive detention times in the waste water treatment facility for the waste water being treated in order to obtain water suitable for discharge to the environment or to a municipal waste water treatment facility for polishing. In addition, many purely bioremediation processes rely primarily on the use of enzymes and bacteria naturally occurring in the waste water to perform the bioremediation and reclamation of the waste water, and are inherently less reliable due to the fluctuation in microbial populations in waste water samples and types. Further, such treatment processes may stimulate the growth of pathogenic organisms as well as beneficial organisms. Moreover, several known biological waste water treatment methods utilize ambient environmental conditions (e.g., pH, temperature, sunlight to maintain the growth rate of the microorganisms) and can be undesirably affected by changes in such ambient diurnal and seasonal environmental conditions.
As a result of the shortcomings of known waste water treatment processes, there is a need to provide a reliable process and system for treating high-strength liquid organic waste water which is environmentally safe, cost effective, aesthetically acceptable, and has functional use in cold weather.
It is an object of the present invention to provide a process and system for treating high-strength organic waste water which does not require mechanically intensive separation and treatment of the biosolids and liquid high-strength waste water.
It is another object of the present invention to provide a process and system for treating high-strength organic waste which does not require the addition of flocculation agents or other chemicals in order to render the treated waste water suitable for discharge to the environment.
It is yet a further object of the present invention to provide a process and system which provides for the safe, reliable and aesthetically acceptable treatment of organic waste waters by biological means and is fully functional for use in cold climates.
It is even a further object of the present invention to provide a process and system for treating waste water which then has the quality to be reused as surface water such as in streams or for raw water supply.